Deck 14: Manual, Semiautomated and Point-of-Care Testing in Hematology

Question 1

The MCV on a patient is calculated to be 115 fL and the MCHC is 35 g/dL.What,in general terms,must be true of the MCH if it is consistent with the previous two indices?

A)It is impossible to know.
B)It should be in the reference range.
C)It should be below reference range.
D)It should be above reference range.

Answer 1

It should be above reference range.

Question 2

On a standard reticulocyte preparation with new methylene blue,100 of 1000 cells that are counted contain blue-stained granulofilamentous material.The red blood count is 3.22 * 10¹²/L,and the hematocrit is 30%.Calculate the MCV.

A)80 fL
B)93 fL
C)98 fL
D)108 fL

Answer 2

93 fL

Question 3

Any of the following could be an explanation for the invalid hemoglobin (MCH = 50)for Mary Jones in Question 9 except

A)the blood sample is hemolyzed.
B)lipemia is present in the plasma.
C)the patient has hemoglobin S (Hb S).
D)the patient's white count is 150.0 * 109/L.

Answer 3

the blood sample is hemolyzed.

Question 4

Why is it important to have a scrupulously clean hemocytometer when manually counting platelets?

A)So few platelets exist that they can be missed if dirt is present.
B)They are so refractile they can be confused with dirt.
C)Their small size makes them easily confused with dirt.
D)They are easily confused with the red cells that are present.

Question 5

Which of the following red cell indices supports microcytic hypochromic red cell morphology?
MCV (fL)MCH (pg)MCHC (g/dL)

A)120 36 35
B)68 22 28
C)90 30 34
D)75 30 34

Question 6

What is the total volume of one side of a hemocytometer if the ruled area is 3 * 3 mm and the depth is 0.1 mm?

A)0.3 mm3
B)0.9 mm3
C)1.0 mm3
D)9 mm3

Question 7

Which of the following could cause the microhematocrit to be falsely decreased?

A)specimen contaminated with intravenous fluid
B)trapped plasma from abnormally shaped red cells
C)dehydration
D)insufficient centrifugation

Question 8

On a standard reticulocyte preparation with new methylene blue,100 of 1000 cells that are counted contain blue-stained granulofilamentous material.The red blood count is 3.22 * 10¹²/L,and the hematocrit is 30%.Calculate the absolute reticulocyte count.

A)0.32 * 1012/L
B)3.2 * 1012/L
C)32.2 * 1012/L
D)0.99 * 1012/L

Question 9

On a standard reticulocyte preparation with new methylene blue,100 of 1000 cells that are counted contain blue-stained granulofilamentous material.The red blood count is 3.22 * 10¹²/L,and the hematocrit is 30%.Calculate the corrected reticulocyte count.

A)1.5%
B)3.0%
C)6.7%
D)15.0%

Question 10

Twenty cells are counted in one of the nine large squares of a hemocytometer.The sample is diluted 1:10.How many cells are present per mL?

A)200
B)1000
C)2000
D)20,000

Question 11

Which of the following red cell indices supports macrocytic normochromic red cell morphology?
MCV (fL)MCH (pg)MCHC (g/dL)

A)120 36 35
B)68 22 28
C)90 30 34
D)75 30 34

Question 12

In the four large corner squares of a hemocytometer,95,102,105,and 98 white cells were counted from a 1:20 dilution.Select the correct interpretation for the white blood count calculated from these values.

A)normal for infant and elevated for an adult
B)normal for any patient
C)elevated for any patient
D)normal for an infant and decreased for an adult

Question 13

On a standard reticulocyte preparation with new methylene blue,100 of 1000 total cells that are counted contain blue-stained granulofilamentous material.The red blood count is 3.22 * 10¹²/L,and the hematocrit is 30%.Calculate the reticulocyte count as a percentage.

A)0.1%
B)1.0%
C)10.0%
D)100.0%

Question 14

Ten nucleated red blood cells (NRBCs)are found in a blood film when differentiating 100 white cells.What is the corrected white blood count if the automated cell counter printed a count of 10.0 * 10⁹/L?

A)0.91 * 109/L
B)9.1 * 109/L
C)91 * 109/L
D)Ten NRBCs are not enough to require a correction

Question 15

Which of the following red cell indices supports normocytic normochromic red cell morphology?
MCV (fL)MCH (pg)MCHC (g/dL)

A)120 36 35
B)68 22 28
C)90 30 34
D)75 30 34

Question 16

Manual cell counting methods in automated hematology laboratories are used for all of the following except

A)routine testing.
B)very low counts.
C)malfunctioning automated instruments.
D)counting spinal fluids.

Question 17

Interpret the following results (all tests performed manually)on an adult female named Mary Jones.
RBC: 3.22 * 10¹²/L
Hemoglobin: 16.0 g/dL
Hematocrit: 30.0%

A)All are normal.
B)All are decreased.
C)Hemoglobin is elevated and other two are normal.
D)Values do not agree with the "rule of three."

Question 18

The calculated indices on Mary Jones from Question 9 are
MCV (fL)MCH (pg)MCHC (g/dL)

A)93 50 53
B)105 29 37
C)93 22 28
D)105 34 35

Question 19

In the center square on one side of a hemocytometer,100 platelets were found;200 were found in the center square on the other side.Select the best course of action.

A)Report the count as 150 * 109/L.
B)Verify the count by estimating the platelet number on the blood film.
C)Recount the hemocytometer on a phase microscope.
D)Repeat the procedure-the two counts are not close enough.

Question 20

The platelet count from the automated cell counter is 80 * 10⁹/L.Platelet satellites around neutrophils are observed on the blood film estimate.A sodium citrate tube is drawn,and the count reads 300 * 10⁹/L from the cell counter.What platelet count * 10⁹/L should be reported?

A)80
B)300
C)330
D)The estimated count from the blood film

Question 21

What causes the RBCs to settle faster through the plasma when inflammation or infection is present?

A)Bacteria cause red cells to agglutinate and fall faster.
B)Increased number of neutrophils cause red cells to form rouleaux.
C)Inflammation makes the plasma less viscous.
D)Acute phase reactant proteins disrupt the electrical charge that normally separates cells.

Question 22

A manual WBC count is performed using a system that makes a 1:20 dilution of blood.When the cells in the four large corner mm² of the hemocytometer are counted,the following numbers of cells are obtained: 8,12,9,and 11.What would be the next step?

A)Count the cells in all 9 mm2 of the hemocytometer.
B)Redo the dilution of blood using a new 1:20 dilution.
C)Redo the dilution of blood using a 1:100 dilution.
D)Calculate the count using the values from the 4 mm2 and report the result.

Question 23

Which of the following is a good use of the erythrocyte sedimentation rate (ESR)?

A)Monitor patients with rheumatoid arthritis.
B)Diagnose acute appendicitis.
C)Diagnose multiple myeloma.
D)Monitor patients with osteoarthritis.

Question 24

Which of the following can cause a falsely increased ESR?

A)concentration of anticoagulant increased
B)tube not totally vertical
C)tuberculosis
D)increased plasma viscosity

Question 25

How do sickle cells or spherocytes interfere with the ESR?

A)prevent rouleaux formation, so falsely decrease
B)encourage rouleaux formation, so falsely increase
C)agglutinate and increase red cell mass, so falsely increase
D)decrease plasma viscosity, so falsely decrease

Question 26

A manual hemoglobin is determined on a patient,and the dilution still appears turbid after letting it sit for 15 minutes.The stained blood film is examined,and sickle cells are observed on the blood film.Equal volumes of the diluted hemoglobin sample and water are mixed together,and the absorbance of this read on a spectrophotometer.How should the hemoglobin result be determined from the standard calibrated graph?

A)Add the results from the turbid and second dilution together and divide by 2.
B)Multiply the result obtained from the graph on the diluted specimen by 2.
C)Divide the result obtained from the graph on the diluted specimen by 2.
D)There was no reason to perform this second dilution.

Question 27

Which regulatory standards mandate the concept of "test site neutrality" for all laboratory procedures?

A)OSHA
B)CLIA
C)Joint Commissions
D)CAP

Question 28

On a standard reticulocyte preparation with new methylene blue,100 of 1000 cells that are counted contain blue-stained granulofilamentous material.The red blood count is 3.22 * 10¹²/L,and the hematocrit is 30%.Calculate the reticulocyte production index (RPI).

A)1.5
B)2.7
C)3.4
D)13.4

Question 29

A 1:20 dilution of blood is made for a white count,and the following number of cells counted in the four large corner mm² of the hemocytometer: 12,28,18,and 15.What should be done next?

A)Report the white count as 3.7 * 109/L.
B)Clean the hemocytometer and recharge with a well-mixed dilution.
C)Increase the number of mm2 counted.
D)Compare this cell count to the one on the other side.

Question 30

Diagnostic testing at or near the site of patient care is known as

A)preanalytic testing.
B)point-of-care testing (POCT).
C)waived testing.
D)Clinical Laboratory Improvement Amendments (CLIA) testing.